All-solid-state laser gyroscope and unlocking method

Abstract

The invention provides an all-solid-state laser gyroscope and an unlocking method. The method comprises the following steps: presetting a frequency difference between two paths of laser, and transmitting and repeatedly oscillating the two paths of laser with the preset frequency difference in different directions in a resonant cavity of the laser gyroscope; and change information of interference fringes formed by the two paths of laser after repeated oscillation is detected, so that carrier rotation information is obtained. The all-solid-state laser gyroscope comprises a laser generation module, a frequency modulation module, a resonance light path module, a photoelectric detection module and a light path supporting module, a laser source of the laser generation module is located outside a closed light path, the frequency modulation module is used for presetting the frequency difference of two paths of laser, and then the laser enters the resonance light path module for repeated oscillation; therefore, the lock area is eliminated. The lock can be unlocked without mechanical shaking, and the all-solid-state laser gyroscope can be realized.

Description

Technical Field

[0001] The invention relates to the technical field of inertial navigation, and in particular to an all-solid-state laser gyroscope and a method for unlocking the gyroscope. Background Art

[0002] At present, the laser gyroscopes commonly used in the market generally use mechanical dithering as the unlocking method. The gain medium is usually placed inside the cavity, and He and Ne gases are generally used as gain media.

[0003] The mechanical jitter unlocking method will interfere with the normal operation of other control systems in some application scenarios. At the same time, the amplitude of mechanical jitter is easily reduced by the life attenuation of piezoelectric ceramics, resulting in unlocking failure. The gas gain medium is not easy to seal and is prone to leakage, causing gyroscope failure. Summary of the invention

[0004] In view of this, the present invention provides a new all-solid-state laser gyroscope and unlocking method, which uses a preset forward and reverse optical frequency difference to unlock, thereby eliminating mechanical jitter and realizing an all-solid-state laser gyroscope.

[0005] In order to solve the above technical problems, the present invention is implemented as follows.

[0006] A fully solid-state laser gyroscope comprises: a laser generating module, a frequency modulation module, a resonant optical path module, and a photoelectric detection module; the laser source of the laser generating module is located outside the closed optical path;

[0007] The laser generating module is used to generate laser light and divide it into two paths, which are introduced into the closed optical path of the resonant optical path module;

[0008] The frequency modulation module is used to preset the frequency difference between the two lasers by modulating the frequency of the lasers to eliminate the locked area;

[0009] The resonant optical path module provides a resonant cavity to generate a closed optical path, which is used to transmit and oscillate two lasers with a frequency difference in forward and reverse directions;

[0010] The photoelectric detection module is used to detect the change information of the interference fringes formed by the laser signal output by the resonant optical path module.

[0011] Preferably, the frequency modulation module modulates the frequency of one of the two lasers generated by the laser generating module, so that the two lasers have the frequency difference after frequency modulation; the frequency difference of the two lasers after modulation is: a fixed frequency difference, or an alternating frequency difference.

[0012] Preferably, the laser generating module comprises a laser, a laser shaping component and a beam splitting component; the laser generates laser light, which is shaped and transformed by the laser shaping component and then divided into two paths by the beam splitting component.

[0013] Preferably, the spectroscopic component includes a spectroscope and a reflector; there are one or more spectroscopes, which are all or partially placed in a closed optical path; the frequency modulation module performs modulation before the laser enters the closed optical path, or after the laser enters the closed optical path.

[0014] Preferably, the light splitting component is a beam splitter and a reflector, the beam splitter is arranged on a closed optical path, and reflects and transmits the incident laser; the reflected laser is directly reflected into the closed optical path of the resonant optical path module, the transmitted laser is first frequency modulated by the frequency modulation module and then reflected back to the beam splitter through the reflector, and is further introduced into the closed optical path of the resonant optical path module by the beam splitter; the two laser beams entering the resonant optical path module are transmitted and repeatedly oscillated in the closed optical path in a clockwise direction and a counterclockwise direction respectively;

[0015] Alternatively, the beam splitting component is a combination of multiple beam splitters + reflectors; the first beam splitter splits the incident laser into two paths, one laser path enters the second beam splitter arranged on the closed optical path, and is reflected by the second beam splitter into the closed optical path of the resonant optical path module to form a laser in a first direction; the other laser path is frequency modulated by the frequency modulation module, and the propagation direction is adjusted by the reflector to enter the third beam splitter arranged on the closed optical path, and is reflected by the third beam splitter into the closed optical path of the resonant optical path module to form a laser in a second direction; the lasers in two directions are transmitted and oscillated repeatedly in the resonant optical path module.

[0016] Preferably, the laser source is a semiconductor laser, a solid laser, a fiber laser or a gas laser.

[0017] Preferably, the laser source provides a reference light source, the mode is TEM00 mode, the wavelength range is 400nm to 1600nm, and the frequency stability is greater than or equal to 10 -8 , the output laser line width is less than 100kHz.

[0018] Preferably, the installation cavity provided by the all-solid-state laser gyroscope is divided into a light splitting area and a resonance area; the light splitting component of the laser generating module and the frequency modulation module are installed in the light splitting area, and the resonance optical path module is installed in the resonance area.

[0019] Preferably, a light source installation position and a resonant optical path module installation position are provided on the installation cavity;

[0020] The laser generating module, except for the light splitting component, is installed at the light source installation position to introduce laser into the internal installation cavity;

[0021] The resonant optical path module installation positions are distributed around the installation cavity in multiple numbers according to the number of reflectors in the resonant optical path module;

[0022] The resonance zone surrounds the periphery of the splitting zone, and the resonance zone and the splitting zone have an intersection zone. The lens in the splitting component for introducing laser into the closed optical path is arranged in the intersection zone; after the splitting component and the frequency modulation module in the splitting zone complete the splitting and frequency modulation, two lasers with preset difference frequencies are introduced into the resonance zone for oscillation.

[0023] The present invention also provides a method for unlocking a laser gyroscope, the method comprising: generating two lasers, and frequency modulating the lasers so that the two lasers are preset with a frequency difference for eliminating the locked area;

[0024] Two laser beams with preset difference frequencies are transmitted and oscillated repeatedly in different directions in the resonant cavity of the laser gyroscope, and the change information of the interference fringes formed by the two laser beams after repeated oscillation is detected.

[0025] Beneficial effects:

[0026] (1) The present invention provides a fully solid-state laser gyroscope, which eliminates the lock zone by presetting the forward and reverse optical frequency difference and directly generating a certain frequency difference before the forward and reverse lasers enter the resonant cavity. The present invention can realize a fully solid-state gyroscope, without mechanical jitter, and will not cause interference to other synchronous systems. Even at low speeds, there is no situation where the forward and reverse light cannot be distinguished, thereby realizing a high-precision laser gyroscope. If the frequency difference adopts an electro-optical modulator, it can be obtained by controlling the electro-optical modulator by an electrical signal, and the modulation is simple.

[0027] (2) The structure of the present invention sets the laser source of the laser generating module outside the resonant cavity. The external laser can be implemented by a semiconductor laser, a solid laser, a fiber laser or a gas laser, with a wide range of options. When a gas laser is not used, the problem of the gas gain medium being difficult to seal and prone to leakage caused by the use of existing built-in active gas lasers can also be avoided.

[0028] (3) This method has a simple principle, requires fewer components, and has a simple process, which can effectively reduce product costs and improve product reliability.

[0029] (4) In a preferred embodiment, two implementation schemes of splitter components are provided. By combining different splitter components, the frequency modulation module can be arranged outside the resonant cavity or inside the resonant cavity, and can be flexibly selected according to the actual space.

[0030] (5) The frequency difference between the two laser beams can be a fixed frequency difference or an alternating frequency difference, which is selected according to the environmental stability. In the case of environmental changes, the use of an alternating frequency difference is conducive to offsetting external disturbance errors, making it easier to implement control and improving the detection robustness of the gyroscope. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1The figure is a block diagram of the composition of the all-solid-state laser gyroscope of the present invention.

[0032] Figure 2 This is a schematic diagram of the structure of an all-solid-state laser gyroscope according to Embodiment 1 of the present invention.

[0033] Figure 3 for Figure 2 Schematic diagram of the laser generation module and frequency modulation module.

[0034] Figure 4 The figure is a schematic diagram of the principle of a resonant optical path module for generating a quadrilateral resonant optical path.

[0035] Figure 5 Schematic diagram of the photoelectric detection module of the present invention.

[0036] Figure 6 This is a schematic diagram of the principle of an all-solid-state laser gyroscope according to the second embodiment of the present invention.

[0037] Figure 7 This is a structural diagram of an all-solid-state laser gyroscope according to Embodiment 1 of the present invention.

[0038] Figure 8 This is a structural diagram of an all-solid-state laser gyroscope according to the second embodiment of the present invention. DETAILED DESCRIPTION

[0039] The present invention is described in detail below with reference to the accompanying drawings and embodiments.

[0040] The laser gyro is installed on the carrier. When the two forward and reverse light beams in the resonant cavity optical path rotate at a small angular rate, the frequency difference formed by the two light beams cannot be distinguished, resulting in the loss of the carrier's rotation information. This section of the carrier rotation rate that cannot produce a distinguishable optical frequency difference is called the lock zone. The conventional method to solve the lock zone is to apply a certain mechanical jitter to the resonant cavity (resonant optical path module) so that the low-speed rotation signal of the carrier is superimposed with the high-speed jitter signal, and then demodulate it through a certain method in the later stage to obtain the low-speed rotation signal. Although this method eliminates the lock zone, it brings additional mechanical jitter to the resonant cavity, which will interfere with the stable operation of other systems in some applications.

[0041] The present invention provides a fully solid-state laser gyroscope, which uses a frequency modulation module to preset the optical frequency difference in the forward and reverse lasers to eliminate the lock area, so as to realize the fully solid-state gyroscope. Because there is no mechanical jitter, it will not interfere with other synchronous systems. Even at low speeds, there is no situation where the forward and reverse light cannot be distinguished, and the high precision of the laser gyroscope can be achieved. At the same time, this method is simple in principle, requires fewer components, and has a simple process, which can effectively reduce product costs and improve product reliability.

[0042] Figure 1FIG. 2 shows a block diagram of the composition of the all-solid-state laser gyroscope of the present invention. Figure 1 As shown, it includes a laser generation module, a frequency modulation module, a resonant optical path module, and a photoelectric detection module. The laser source of the laser generation module is located outside the closed optical path.

[0043] The laser generating module is used to generate laser light and divide it into two paths, which are introduced into the closed optical path of the resonant optical path module.

[0044] The frequency modulation module is used to modulate the laser frequency, thereby presetting the frequency difference between the two lasers to eliminate the lock area; the frequency difference can be a fixed frequency difference or an alternating frequency difference, which is selected according to the environmental stability. The alternating frequency difference is suitable for occasions where the environmental changes are unstable, and the fluctuation error with the environmental changes is easier to control.

[0045] The resonant optical path module provides a resonant cavity to generate a closed optical path, which is used to transmit and oscillate two lasers with a frequency difference in forward and reverse directions;

[0046] The photoelectric detection module is used to detect the change information of the interference fringes formed by the laser signal output by the resonant optical path module, and is used by the subsequent circuit system to obtain the carrier rotation information according to the change of the interference fringes.

[0047] The above modules can be supported and fixed by the mounting cavity provided by the all-solid-state laser gyroscope. The mounting cavity is preferably an integrated structure, or a split structure.

[0048] like Figure 3 As shown, in a preferred embodiment, the laser generating module specifically includes a laser, a laser shaping component, and a beam splitter component; the laser generates laser light, which is shaped and transformed by the laser shaping component, such as collimation, linear polarization conversion, polarization direction conversion, etc. The adjusted laser light is divided into two paths by the beam splitter component and introduced into the closed optical path provided by the resonant optical path module. The frequency adjustment module can insert the difference frequency after the beam splitter component divides the light into two paths and before the repeated oscillation starts in the resonant cavity; the laser light can be modulated before entering the closed optical path, or after entering the closed optical path. The frequency modulation module can be set inside or outside the resonant cavity of the resonant optical path module.

[0049] The laser provides a reference light source. In a preferred embodiment, the laser mode is TEM00 mode, the wavelength range is 400nm to 1600nm, and the frequency stability is greater than or equal to 10 -8 , the output laser line width is less than 100kHz.

[0050] The laser can be a semiconductor laser, solid laser, fiber laser or gas laser, with a wide range of options. When gas lasers are not used, the problem of difficult sealing and easy leakage of gas gain medium caused by the existing built-in active gas lasers can be avoided. The laser as a light source can be set in the gyroscope cavity, or it can be set outside the cavity, or installed on the cavity (such as Figure 7 and Figure 8 ).

[0051] In a preferred embodiment, the laser shaping assembly includes a collimating lens, a polarizer and a 1 / 2 wave plate, see Figure 3 The collimating lens shapes the laser into nearly parallel light to reduce energy dissipation; the polarizer converts the laser into linear polarized light, and adjusts the polarization direction through the 1 / 2 wave plate to adapt to the required polarization state of the resonant optical path module; the beam splitter splits the laser beam into two beams, one of which passes through the frequency modulation module to change the original laser frequency to form a laser with a frequency difference with the other laser beam. The two laser beams enter the resonant optical path module in a clockwise direction and a counterclockwise direction respectively.

[0052] The spectrometer is used to achieve the splitting and propagation direction adjustment. The spectrometer is a combination of a spectroscope and a reflector. There are one or more spectroscopes, all or part of which are placed in a closed optical path; the frequency modulation module cooperates with the spectroscope to inject the difference frequency after the laser is split into two paths and before entering the closed optical path for repeated oscillation. In practice, the specific structure of the spectroscope is not limited, as long as it can split a laser beam into two and introduce the two laser paths into the closed optical path.

[0053] Figure 3 FIG. 2 shows a partial structure of a gyroscope according to an embodiment of the present invention, including an implementation of a light splitting component. Figure 3 As shown, the light splitting component in this scheme is composed of 3 light splitters + a reflector, combined with Figure 2 As shown, two beam splitters are arranged on the closed optical path of the resonant optical path module, and a beam splitter, a reflector and a frequency modulation module are arranged outside the closed optical path. Among them, beam splitter 1 divides the incident laser into two paths, one path enters beam splitter 2, and is reflected by beam splitter 2 into the closed optical path of the resonant optical path module to form a laser in the first direction (clockwise in the figure); the other path first passes through the frequency modulation module, and then enters beam splitter 3, and is reflected by beam splitter 3 into the closed optical path of the resonant optical path module to form a laser in the second direction (counterclockwise in the figure); the lasers in the two directions are transmitted and oscillated repeatedly in the resonant optical path module. Beam splitter 2 and beam splitter 3 are arranged in the closed optical path to transmit and propagate the laser.

[0054] Figure 6The gyroscope principle of the second embodiment of the present invention is shown, wherein the light splitting component is a beam splitter and a reflector, and the beam splitter is arranged on a closed optical path; the beam splitter reflects and transmits the incident laser, and the reflected laser is directly reflected into the closed optical path of the resonant optical path module, and the transmitted laser is first frequency modulated by the frequency modulation module and then reflected back to the beam splitter through the reflector, and reflected by the beam splitter into the closed optical path of the resonant optical path module; the two laser beams entering the resonant optical path module are transmitted and repeatedly oscillated in the resonant optical path module in clockwise and counterclockwise directions respectively. The device of this solution is more simplified, and the reflector and frequency modulation module are located in the resonant cavity, which is conducive to miniaturization.

[0055] Figure 3 and Figure 6 The necessary beam splitting components of the two schemes are shown, which does not mean that other lenses or components are not allowed to be added in the optical path. In addition, both schemes set a beam splitter in the closed optical path to facilitate the introduction of laser. In practice, other methods can also be used to introduce laser.

[0056] The frequency modulation module is used to adjust the frequency of the laser so that the two laser beams transmitted in the closed optical path have a frequency difference. The frequency modulation module can use an optoelectronic modulator or an acousto-optic modulator. The optoelectronic modulator can be controlled by an electrical signal, and the control is more accurate and simple.

[0057] In order to facilitate adjustment and reduce the use of frequency modulation modules, a frequency modulation module can be used to modulate the frequency of one of the two laser beams after the splitting. Preferably, the frequency of one of the light waves reaches about 2MHz. By applying different control signals to the frequency modulation module, a laser with alternating frequency or a laser with constant frequency can be generated, thereby causing the two laser beams to produce an alternating frequency difference or a constant frequency difference, which is used to eliminate the gyro lock area. The frequency change of the laser after passing through the frequency modulation module is preferably less than 10MHz.

[0058] Optical devices or laser processing modules can be added before or after the optical path where the frequency modulation module is located to achieve changes in the optical path or control / improve the performance of the laser. Figure 3 and Figure 6 The location of the frequency modulation module shown is convenient for designing the optical path and reducing the size of the device.

[0059] In practice, two frequency modulation modules can also be used to achieve frequency difference modulation, and the two signal frequencies are synchronously applied in opposite directions. The control of the two frequency modulation modules is more flexible, but the cost is increased.

[0060] The resonant optical path module provides a resonant cavity, which is mainly used to form a closed optical path system. Two laser beams are transmitted in the resonant cavity in positive and negative directions along the closed optical path. The two laser beams can oscillate repeatedly inside the resonant optical path module to form an interference-enhanced resonant field. Figure 4 A schematic diagram of a resonant optical path module of a quadrilateral resonant optical path is shown. The resonant optical path module in this example is composed of four reflectors, which form a quadrilateral closed optical path. The four reflectors are composed of 2 spherical reflectors and 2 plane reflectors, which are symmetrically placed, and each reflector is attached to the support module at a certain angle. In order to reduce the optical path loss, the installation angle error of each mirror is required to be less than 5". In order to ensure the stability of the optical path in high and low temperature environments, the materials of the reflective lens and the support module use materials with good temperature coefficients, such as microcrystalline glass, quartz glass materials, etc. The lens can be fixed in the cavity by epoxy glue.

[0061] In practice, the specific implementation of the resonant optical path module is not limited, as long as the optical path is closed. The combination of multiple reflectors can also be selected according to needs. The quadrilateral closed optical path can also use a polygonal optical path such as a triangle or a pentagon.

[0062] The photoelectric detection module is mainly used to convert the forward and reverse light of the laser output from the resonant optical path module into one direction, and use a photoelectric detection sensor to detect the change information of the interference fringes finally formed. Figure 5 FIG. 1 shows a schematic diagram of the implementation structure of a photoelectric detection module. Figure 5 As shown in the figure, the photoelectric detection module consists of a light combining mirror and a photodetector. The light combining mirror is placed on the back of the plane reflector of the resonant light path module, and combines the forward light and the reverse light in the resonant light path into one direction to generate a beat frequency signal. The photodetector is placed at the light spot output position after the light combining mirror, and is used to detect the movement information of the interference fringes generated by the combined light, and obtain the rotation information of the carrier through the post-processing circuit.

[0063] In practice, the light combining mirror of the photoelectric detection module can be replaced by other components or a modulation device of an auxiliary optical path can be added. For example, a component composed of independent optical elements can be used as long as it can combine the two laser beams in the closed optical path for output.

[0064] The shape of the mounting cavity of the all-solid-state laser gyroscope is designed according to the position of the above modules, and the structure is not unique. In order to ensure the stability of the optical path in high and low temperature environments, the material of the mounting cavity uses a material with a good temperature coefficient, such as microcrystalline glass and quartz glass.

[0065] Figure 3 , Figure 4 and Figure 5 constitutes Figure 2 For a specific implementation of the first embodiment, see Figure 2The scheme adopts a laser light source; a collimating lens is used to convert the laser output into nearly parallel light, reducing the energy loss caused by laser divergence; a polarizer converts the output laser into linearly polarized light, ensuring the stability of laser interference, while adapting to the polarization state of the lens coating to reduce the laser loss in the ring cavity; a 1 / 2 wave plate rotates the polarization plane of the incident light by 45°, and the return light rotates to 90°, forming an effective optical isolator with the polarizer to prevent the return light from entering the interior of the semiconductor laser and causing unstable laser output. Beam splitter 1 decomposes the original laser beam into two beams, and beam splitter 2 and beam splitter 3 divide the input laser into forward laser and reverse laser, which run in a quadrilateral ring cavity constructed by a plane reflector and a spherical reflector; the frequency modulation module adopts an optoelectronic modulator, which changes the light wave frequency of one of the forward light or the reverse light, so that the frequency difference between the two beams changes by less than 10MHz. The drive control mode of the optoelectronic modulator is constant frequency control or alternating frequency control, which is used to eliminate the lock area in the laser gyroscope; the two plane reflectors and the spherical reflector in the resonant cavity optical path are placed at an angle of 45° to form a quadrilateral resonant optical path, and the plane reflector at the installation location of the photoelectric detection module is partially transparent for information detection, and the spherical reflector is a full-reflection mirror to reduce the loss in the cavity; the light combining mirror combines the forward and reverse light together to facilitate the detection of the rotation information of the carrier. The light combining optical path is as follows Figure 5 The internal optical path of the combined optical mirror is shown in the figure; the photodetector converts the optical signal with rotation information into an electrical signal, which is processed by the subsequent amplifier circuit, demodulation circuit, counting circuit, etc., and finally gives the rotation information of the carrier.

[0066] Figure 7 The structure diagram of the all-solid-state laser gyroscope of the first embodiment is shown, corresponding to Figure 2 The principle, such as Figure 7 As shown, the mounting cavity 1 provides mounting positions 13 for various devices. The mounting cavity 1 is divided into a light splitting area and a resonance area. The light splitting component and the frequency modulation module of the laser generating module are mounted in the light splitting area, and the resonance optical path module is mounted in the resonance area.

[0067] Preferably, the resonance area surrounds the periphery of the light splitting area, making full use of the space and reducing the overall volume. The resonance area and the light splitting area have an intersection area, and the lens used to introduce the laser into the closed optical path in the light splitting component is arranged in the intersection area. After the light splitting component and the frequency modulation module in the light splitting area complete the light splitting and frequency modulation, the two lasers with the preset difference frequency are introduced into the resonance area for oscillation.

[0068] Preferably, a light source mounting position and a resonant optical path module mounting position are set on the mounting cavity; the laser generating module except the part of the splitter component is installed at the light source mounting position to introduce laser into the internal mounting cavity; the resonant optical path module mounting position is distributed in multiple locations around the mounting cavity according to the number of reflectors in the resonant optical path module; the reflective surface of the reflector faces the inside of the mounting cavity.

[0069] Specifically, the laser and laser shaping components of the laser generating module are integrated together to form a laser generating and shaping integrated structure 2, which is installed at the light source installation position provided by the mounting cavity 1. One end of the laser generating and shaping integrated structure 2 is located outside the mounting cavity 1 for connecting the circuit; the other end extends into the mounting cavity 1 to emit shaping laser into the cavity. The four reflectors in the resonant optical path module include two spherical reflectors 3 and two plane reflectors 4, which are arranged in the resonance zone. The mounting cavity 1 provides four installation positions for installing these reflectors, and the reflective surface of the reflector faces the inside of the mounting cavity. The light combining mirror 8 is arranged at one of the mirror positions, which is arranged at a plane reflector 4 position here, and is arranged outside the mounting cavity 1 so as to connect the photodetector 9. The photodetector 9 is located outside the mounting cavity 1 for easy lead-in.

[0070] The spectroscopic component in the laser generating module includes a reflector 6 and three spectroscopes 7. These four mirrors together with the frequency modulation module 5 are arranged in the spectroscopic area. Among them, the first spectroscope is arranged in front of the laser generating shaping integrated structure 2, and is used to divide the incident laser into two paths, one laser A is incident on the frequency modulation module 5, and the other laser B is incident on the second spectroscope. The laser B' modulated by the frequency modulation module 5 is incident on the third spectroscope; the second spectroscope and the third spectroscope are arranged in a closed optical path, refracting the incoming laser, introducing the difference frequency laser into the closed optical path, and oscillating repeatedly. The spectroscopic area of ​​the mounting cavity 1 can adopt an open structure, and a cover plate 10 is provided to prevent the internal components from being contaminated, and at the same time facilitate debugging and replacement of components. The entire resonant cavity is filled with dry gas such as nitrogen, and the air pressure is 1 atmosphere. The resonance area is provided with a capillary 12 to realize the transmission of light. The capillary 12 is provided on the central surface of the mounting cavity, and an aperture hole 11 is provided at any position of the capillary 12. The mounting position of each component may be in the form of a groove, such as a beam splitter, a frequency modulation module, and a reflector placement groove 13. Through the design of the placement groove, it is ensured that the center of the component is coplanar with the capillary optical path.

[0071] Figure 8 The structure diagram of the all-solid-state laser gyroscope of the second embodiment is shown, corresponding to Figure 6 The structure of this embodiment is different from that of the first embodiment in the composition and position relationship of the light splitting component and the frequency modulation module. Figure 8 As shown, the mounting cavity 01 provides mounting positions 013 for various devices. The mounting cavity 01 also provides a splitting area and a resonance area, and the resonance area surrounds the periphery of the splitting area. The splitting component and the frequency modulation module of the laser generating module are arranged in the splitting area, and the resonance optical path module is arranged in the resonance area. The splitting component includes a splitter 07 and a reflector 06. The splitter 07 is arranged on the closed optical path of the resonance area to introduce two laser beams with a preset difference frequency into the closed optical path of the resonance area.

[0072] Specifically, the laser and laser shaping components of the laser generating module are integrated together to form a laser generating and shaping integrated structure 02, which is installed on the mounting cavity 01. One end of the laser generating and shaping integrated structure 02 is located outside the mounting cavity 01, and the other end extends into the mounting cavity 01 to emit shaping laser into the cavity. The four reflectors in the resonant optical path module include two spherical reflectors 03 and two plane reflectors 04, which are arranged in the resonance zone. The mounting cavity 01 provides four mounting positions for installing these reflectors. The light combining mirror 08 is arranged at one of the mirror positions, which is arranged at a plane reflector 04 position and is arranged outside the mounting cavity 01. The photodetector 09 is connected to the light combining mirror 08.

[0073] In this embodiment, the spectroscopic component in the laser generating module includes a reflector 06 and a spectroscope 07, and these two mirrors together with the frequency modulation module 05 are arranged in the spectroscopic area. Among them, the spectroscope 07 is arranged in front of the laser generating shaping integrated structure 02, and is used to divide the incident laser into two paths, one laser A is incident on the closed optical path, and the other laser B is incident on the frequency modulation module 05. The reflector 06 is arranged in front of the frequency modulation module 05, and the laser B' modulated by the frequency modulation module 05 is reflected back to the spectroscope 07 through the reflector 06, and introduced into the closed optical path by the spectroscope 07. Laser A and laser B' have a preset difference frequency and oscillate repeatedly in the closed optical path. Similarly, in this embodiment, the spectroscopic area of ​​the mounting cavity 01 can adopt an open structure, and a cover plate 010 is provided. The capillary hole 012 is opened in the resonance area to realize the transmission of light. The capillary hole is on the central plane of the mounting cavity, and an aperture hole 011 is opened at any position of the capillary hole 012. The mounting position of each component can appear in the form of a groove, such as the beam splitter, frequency modulation module, and reflector placement groove 013. Through the design of the placement groove, it is ensured that the center of the part is coplanar with the capillary optical path.

[0074] The above specific embodiments only describe the design principle of the present invention. The shapes and names of the components in the description may be different and are not limited. Therefore, those skilled in the art in the field of the present invention may modify or replace the technical solutions recorded in the above embodiments; and these modifications and replacements do not deviate from the creative purpose and technical solutions of the present invention and should all fall within the protection scope of the present invention.

Claims

1. An all-solid-state laser gyroscope, characterized in that: include: Laser generation module, frequency modulation module, resonant optical path module, photoelectric detection module; the laser source of the laser generation module is located outside the closed optical path; The laser generating module is used to generate laser light and divide it into two paths, which are introduced into the closed optical path of the resonant optical path module; The frequency modulation module is used to preset the frequency difference between the two lasers by modulating the frequency of the lasers to eliminate the locked area; The resonant optical path module provides a resonant cavity to generate a closed optical path, which is used to transmit and oscillate two lasers with a frequency difference in forward and reverse directions; The photoelectric detection module is used to detect the change information of the interference fringes formed by the laser signal output by the resonant optical path module.

2. The all-solid-state laser gyroscope according to claim 1, characterized in that: The frequency modulation module modulates the frequency of one of the two lasers generated by the laser generating module, so that the two lasers have the frequency difference after the frequency modulation; the frequency difference of the two lasers after the modulation is: a fixed frequency difference or an alternating frequency difference.

3. The all-solid-state laser gyroscope according to claim 1, characterized in that: The laser generating module comprises a laser, a laser shaping component and a light splitting component; the laser generates laser light, which is shaped and transformed by the laser shaping component and then divided into two paths by the light splitting component.

4. The all-solid-state laser gyroscope according to claim 3, characterized in that: The beam splitter assembly includes a beam splitter and a reflector; there is one or more beam splitters, all or part of which are placed in a closed optical path; the frequency modulation module performs modulation before the laser enters the closed optical path, or after the laser enters the closed optical path.

5. The all-solid-state laser gyroscope according to claim 4, characterized in that: The light splitting component is a beam splitter and a reflector. The beam splitter is arranged on a closed optical path to reflect and transmit the incident laser. The reflected laser is directly reflected into the closed optical path of the resonant optical path module. The transmitted laser is first frequency modulated by the frequency modulation module and then reflected back to the beam splitter through the reflector, and is further introduced into the closed optical path of the resonant optical path module by the beam splitter. The two laser beams entering the resonant optical path module are transmitted and oscillated repeatedly in the closed optical path in clockwise and counterclockwise directions respectively; Alternatively, the beam splitting component is a combination of multiple beam splitters + reflectors; the first beam splitter splits the incident laser into two paths, one laser path enters the second beam splitter arranged on the closed optical path, and is reflected by the second beam splitter into the closed optical path of the resonant optical path module to form a laser in a first direction; the other laser path is frequency modulated by the frequency modulation module, and the propagation direction is adjusted by the reflector to enter the third beam splitter arranged on the closed optical path, and is reflected by the third beam splitter into the closed optical path of the resonant optical path module to form a laser in a second direction; the lasers in two directions are transmitted and oscillated repeatedly in the resonant optical path module.

6. The all-solid-state laser gyroscope according to claim 1, characterized in that: The laser source is a semiconductor laser, a solid laser, a fiber laser or a gas laser.

7. The all-solid-state laser gyroscope according to claim 1, characterized in that: The laser source provides a reference light source, the mode is TEM00 mode, the wavelength range is 400nm to 1600nm, and the frequency stability is greater than or equal to 10 -8 , the output laser line width is less than 100kHz.

8. The all-solid-state laser gyroscope according to any one of claims 1 to 7, characterized in that: The installation cavity provided by the all-solid-state laser gyroscope is divided into a light splitting area and a resonance area; the light splitting component of the laser generating module and the frequency modulation module are installed in the light splitting area, and the resonance optical path module is installed in the resonance area.

9. The all-solid-state laser gyroscope according to claim 8, characterized in that: The installation cavity is provided with a light source installation position and a resonant optical path module installation position; The laser generating module, except for the light splitting component, is installed at the light source installation position to introduce laser into the internal installation cavity; The resonant optical path module installation positions are distributed around the installation cavity in multiple numbers according to the number of reflectors in the resonant optical path module; The resonance zone surrounds the periphery of the splitting zone, and the resonance zone and the splitting zone have an intersection zone. The lens in the splitting component for introducing laser into the closed optical path is arranged in the intersection zone; after the splitting component and the frequency modulation module in the splitting zone complete the splitting and frequency modulation, two lasers with preset difference frequencies are introduced into the resonance zone for oscillation.

10. A method for unlocking a laser gyroscope, characterized in that: The method comprises: generating two lasers, and frequency modulating the lasers so that the two lasers are preset with a frequency difference for eliminating the locked area; Two laser beams with preset difference frequencies are transmitted and oscillated repeatedly in different directions in the resonant cavity of the laser gyroscope, and the change information of the interference fringes formed by the two laser beams after repeated oscillation is detected.

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